1. Field of the Invention
The invention relates to the field of spread spectrum communications.
2. Prior Art
Digital communications over power lines as well as other media using a spread spectrum signal which relies on correlation for the detection of the digital signals is well known. For example, see U.S. Pat. No. 4,979,183. Other examples of such communications can be found in U.S. Pat. Nos. 5,289,498; 5,263,050; 5,090,024; 5,278,862 and 5,359,625.
The spread spectrum signal can in some cases be distorted, particularly on power lines. For example, a power supply in a television can sufficiently distort the signal to cause misdetections. The present invention provides an apparatus and method for dealing with this distortion by, in general terms, dividing or splitting the broad band, spread spectrum signal into sub-bands and separately processing the sub-bands before recombining the sub-bands. The separate processing of signals in different sub-bands is known in the prior art, for example see U.S. Pat. No. 3,112,452. As will be seen the present invention provides a unique method and apparatus for using split-band techniques for spread spectrum communications.